DP #24 Engine failure....
 

Ok, so I feel compelled to post this #1 for many other DP Owners out there, Ma Mopar, and Gary Stanton as well as several component vendors while I may never be a fan of I would have bet just about anything their issues caused ours.

These were not the cases.

The circumstances of the failure were as follows.
The car came out of the water at 8000 rpm give or take. My issue for lack of a burnout limiter.
It freespun, no load.
Rods exited the pan.
We were having issues with oil pressure or so we may have thought, we are still unsure about the sender / gauge combo.
We had a 3 quart accumulator in place and functioning correctly.

We took apart #24 DOA Engine #2 Here is what we found.

#3 Smacked an Exhaust valve HARD
Minor/Minimal scoring to the journal on #3 (dono about #4 will have to cut that one off)
Some bluing to #3 rod. top half
NO Breakage of Rod, or cap, both intact.
Bolts both broke at mating surface.
#4 Rod Z'd from the impact of the #3 Rod and Wristpin exiting the engine in castaspophic fasion. (a very intersting sight, it looks like it was made that way) and 100% intact. just well z'd to the wrong journal.
The rest of the engine internals took massive damage as it looks like (as in we cant find and there is a lot of metal unaccounted for the wrist pin of #3) shattered or was scattered around everywhere.
It appears the bolts sheared on #3 the assmebly broke free of the crank, on a subseqent rotation, (from the side scar on the crank) the crank smacked the rod from the side, and disloged the pin from the bottom of the piston.

All rest of the engine journals and bearings looked as would be expected on an engine that had full oil flow and only 6 or 7 passes, excellent to just like they should, no galling, no scoring, no oddities of any sort, Id run em again in an instant....that nice.

No damage (visible) to cam other than a bent pin. Billet Gundrilled cam, being sent back to manufacturer to be checked for microcracks/straighness and suitablity to be run again.

Someone who was present called before I tore the heads off and said "Ive thought about it an I think you smacked that valve hard and things went bad from there" I thought about it and I agreed maybe...

After much thought and discussion here is OUR , Me and the Old Mans conculsion. With someones initial and correct call (I would mention their name but I didnt ask them if I could)

The smack on #3 at 8000 (or where ever it happened below that) set things in motion as was suggested.

Cam backlash is where I come up, we are not using a stock chain but a double roller, and there is much more play in it than a "fresh" setup, the follower/tensioner design is adequate but was designed for street use, even in the aftermarket setup we are using, when the bottom freespun it backlasked on a very heavy (and ours is 4 lbs lighter than stock) cam, that allowed the tensioner (which its design would allow) to collapse from a ) to a ! this would allow the cam to retard by at least 6 degrees and the exhaust valve made contact. We have a very significant duration and VERY agressive ramp rates.

Clay testing on the engine prior showed adequate not even "marginal" on both in and ex at the advance I was running (4 deg) So...

The springs have a killer rate and pressure and weve had no issues nor has anyone else with them over 8500....

So this conlcusion seems to be the appropriate one.

The Rods (scat) I am actually VERY suprised that any I beam forged rod made in China took....its staggering. They are mutilated but intact not broken.

The workmanship of the assembly in the case of our bottom end, no issues clearances etc all looked to be spot on.

The bolts, well they failed but under the circumstances, I dont know that any wouldnt have.

The timing set and I wont name the vendor is the ONLY item I can look to.....there is a significant lack of availablity and choices for these engines many others with different combos dont have to deal with , that will change but for right now well....were "stuck" short of a custom setup. As well not even the timing set itself but the multi plate ) shaped tesioner that could collpse to a full flat condition, this is both the original and aftermarket design.

These are the things we saw, these are the things we did and these are the conclusions we have come to.

I post them here so as to alleviate any "finger pointing" or "uncertainty"

Some of which I may have caused by what I have said and not said.

I thought the rod gave, and well, I was wrong, it and the cap are intact. bolts broke and the rest was haging through the pan.

And I thought as did my father we had oiling issues, or the potential for them, this was incorrect as well from the clear evidence shown in the engine.

Pictures to follow as we upload them after I get on the road to Houston :D
Ill put Mandie in Charge of that :eek:

The reason it took so long ? Well , weve been busier than you can imagine re-rigging the trailer, broken truck, new engines, and business. So....here it it.....sorry it took so long, I know of one engine guy who has been loving our failures (the engine guy many are sending their DP motors too)

Cheers all

Have a safe and happy easter......

Re: DP #24 Engine failure....
 

If you had a timing chain problem, odds are you would not have one bent valve, but rather eight, or maybe even sixteen.

It is VERY rare for a bent valve to bend a rod, break a piston, or kill a wrist pin.

Bluing of the journal, the bearing, or the rod is a sign of a lubrication problem, and/or a problem with the rod staying round.

Excessive RPM, especially in a burnout, will often over stress the rods, especially on the exhaust stroke where there is little or no resistance to upward piston motion, and only the rod stops it. When a rod bolt shears, it is usually a sign that the bolt was not properly preloaded.

I've never seen a need to spin an engine past 5K in a burnout. I count it as I'm doing a very poor job of driving if I even hit the burnout chip I usually set at 5500.

Re: DP #24 Engine failure....
 

Exactly Right: Alan I would kick the my boys b*tts if I played the run back over 5,500 on burnout

Re: DP #24 Engine failure....
 

Not being "contrary" or arguing just explaining why how what we came to our conclusions.

If you had a timing chain problem, odds are you would not have one bent valve, but rather eight, or maybe even sixteen.

I didnt say it broke I said I believe it backlashed when it freespun this would generally ONLY affect 1 valve , and not even neccesarily 1 , depending on where in the roatation occured.

It is VERY rare for a bent valve to bend a rod, break a piston, or kill a wrist pin.

I didnt say the valve bent, I said it tapped, and our pockets are dead on anglewise and 3/4 the diamater of the valve face. The valve is not bent or stuck (there may be minor runount now of course) but its not "bent" as in at issue. When it contacted as is evident by the very clear impression on the cylinder it was very near tdc, unlike the other and prior valve hit that it with a "hung" valve where the valve did bend and the mark was nearly an inch off.

Nor did I say, or mean to infer a valve broke things, rather the peening of the bearing on the crank started issues which escalated from there.

I said or thought I said, the rod was bent on #4 by the exit of #3, the wrist pin kill and piston issue was caused by the crank shearing the hung rod on a Subsequent roatation while the piston was low in the bore, there is also evidence of this on the bottom of the piston , the crank and the rod.

Bluing of the journal, the bearing, or the rod is a sign of a lubrication problem, and/or a problem with the rod staying round.

Correct, which comes first though ? The chicken or the egg ? In this case we think the smack on the bearing caused by the hard valve tap started what ended up with either the bearing getting peened against the crank,

And there are absolutley no other signs anywhere in the engine of lubrication issues, we were pretty sure we would see them, we my father especially was very suprised not only not to but to see things as well as they were everywhere else.

So, explain why ONLY on the rod where the valve smacked, is there evidence of bluing and perfectly in pocket the tap is (on other engines if it had occured after the rod broke its not usually perfeclty in line with where it should be)

Im being serious and not a dikk , I am curious as to alternative explanations to why on #3 where the valve hit, all the other damage would be centered. and when its pretty clear that #3 hit at TDC or close , we are talking a very small amount, the only thing I can see to account for this would be backlash, OR its possible that the whole debacle was perfectly timed and the rod broke first causing the rod to be propelled upward with the assembly at the exact time the exhaust valve was only say 100 down and the mark was a marvelous coincidence of timing ? Or is it more likley the cam fell slightly retarded in relation to the crank for a moment and this started things in motion ?

If there was no binding or galling of rockers, guides, no bent valve, nothing else and adequate ptv clearance, and no other taps, how else can this be accounted for ?

Excessive RPM, especially in a burnout, will often over stress the rods, especially on the exhaust stroke where there is little or no resistance to upward piston motion, and only the rod stops it.

Agreed.

When a rod bolt shears, it is usually a sign that the bolt was not properly preloaded.

Thats incorrect, In this case, I saw it done on this engine at Stantons facility in person on this engine.

I've never seen a need to spin an engine past 5K in a burnout. I count it as I'm doing a very poor job of driving if I even hit the burnout chip I usually set at 5500

Really only second time in a car ? And at that in a FI car with the setup we have ? It wasnt intentional of course you are correct in that there wasnt a need. Hmmmm.... I wouldnt and it wasnt me driving so. The engine will go from pretty much nothing to 8k at 55% tp in the water. Instantly. So I should have seen it and do as my failure for not anticipating someone else , and we did set the car up for multiple drivers, my fault for not anticipating the need for one. Not the drivers in a NEW and wholly different setup than they are used to.

Re: DP #24 Engine failure....
 

Sorry to hear about your mishap......

Re: DP #24 Engine failure....
 

Roller Chains don't work that way. The slack was probably caused by something wrong in the valve train making it go going harmonic.
Pick something else to blame.
I don't like revs in a free spin too high for the weight/strength ratio of the parts. That usually separates the valve train and makes it unstable, hence loose chain... There is probably other damage in the valve train you havent seen.
I've never seen a valve hitting a piston long enough to blue a rod/rod journal and loose a bearing. Valve head usually breaks off at the valve stem first.
ditto:
On lubrication or pulling the rod out of round. A long time ago.. close to the time you were born. Big block chevies had problems with rod bearings being too tight on the journal at the parting line and when the revs went high they pinched the crank and wiped all the lube off and caused the rod to fail/spin the bearing. I've seen a lot of that in the early days of my business.
I made some good money fixing them where they would last. It would be interesting to do an inspection of the pieces.

Another thing that makes rod bolts fail is excess load by negative G-forces on the piston-Rod assy. To put it bluntly the piston and rod trying to launch into orbit on the Ex stroke with no load. Resulting in a load that is too much for the strength of the bolt. Condition of the parts could determin if this was the case. Also if the burnt/blue of the rod extends into the bolts the heat could have weakend the bolt lowering it's strength and it's yeild point.
Just my .02

Re: DP #24 Engine failure....
 

What gear are you doing burnouts in?....

Use high gear or start in second and quickly shift to high and watch the tach closely..........Starting in low allows the engine to rev much too quickly....,

No need to do a burnout anymore than 500rpm over converter stall

Trying to determine what broke in a major engine blowup is difficult.

If it had spun a bearing it would be easier to diagnose.......but any blueing of the crank or rod has me thinking that is where the event started....

Suffice it to say 8000+ rpm is to high. Any contact between the piston and the valve is enough to start a catastrophic failure.......

Without testing how do you know your engines rpm limits? It is much better and safer to approach that from a conservative side....


Small block Chevs are known for being able to spin very high with ease......Stock solid lifter small blocks could go to 8000rpm or higher.......BUT they did not make power there and they usually broke within a short number of runs at that kind of rpms without many parts upgrades....

Re: DP #24 Engine failure....
 

Burnouts in 2nd and then 3rd as you said. The "target" was 5000-5500 (stall is right around 5200) so yep on target there. The issue was it went to high, that was not intentional.

Now that being said I would agree 100% its difficult to diagnose exactly where it started, that being known the reason for my post was the following

For many of the DP Owners we are in contact with, but its easier to put it here and on the blog than repeat the same thing 25 or 30 times to interested parties.

My plan was.

To provide facts (what we saw)
To provide observations
To provide conclusions we came to, and get feedback,

The facts are immutable, the facts are #3 rod bolts are borked.,
The rods are intact , and didnt break causing the failure itself.
The bearing journals elsewhere looked excellent and didnt suffer mass oil starvation as we expected and THOUGHT we may have encountered.
The wrist pin was torn from the bottom of #3 piston, and shattereed the pieces causing a peppering thoughout the bottom end.

Now conclusions those are both subjective and subject to change...

Others and other DP teams may come to different and more accurate conclusions, hopefully if they do they will share them with us, and we will look at what we have seen and move forward reformulating our conclusions. HOPEFULLY in the end, well....we will ALL get closer to the actual event and ALL be able to learn from it.

I am not big on keeping things "secret" I joke about secret squirrel things, but other than our exact cam profiles, well there is nothing we wont share with other DP team.

So this seemed like as good a place as any to do that.

There have been some very accurate assesments on certain items here that normally I would agree with but other things others arent familiar with, valve train harmonics can be an issue on this engine, but no damage to the valve train elsewhere is present, not even a bent pushrod, the pushrods are a large moly partially tapered and well they are staunch enough to take a massive hit and break the rocker shaft pedastals without bending themselves. So I dono, it dosent mean I will discount it, it means I will in fact look where I may have not.

I appreciate all the feedback and insight, there are things here, some Ive thought of, some I havent.

I will get the pics posted as soon as possible I think they will be a big help.

I guess Phase I was share what we saw with the other DP team.
Phase II is show everyone what happened and while I know it will never be a 100% consensus perhaps its an excersise we all can learn from.

Like my dad says "Were trainable" so....let the ideas flow forth, the other DP teams and us can take what we see, hear and reformulate our conclusions.

My X once asked me and my dad why we do nothing but argue, we looked at each other shocked, I dont think wed had an "argument" in years...Its how we "think" and change our conclusions.

In as much as how do we know the limits ? Well other DP teams are running the same, Dyno testing has showed these engines stable to 8k at no issue with better springs, 72-75 with no issues, the lifters are killers....very cool for a totally stock piece. In our case we had run to 8k under load on the dyno with no issue,.

I would like to see 8 as our limit, needless to say 8k under load and 8k freespinning arent exactly the same :D And the 8k freespin was not intentional.

Re: DP #24 Engine failure....
 

what was the water temp when the failure happened???? cold seize ??? wrist pin pulled from the bottom and broken bolts ,,, gmonde

Re: DP #24 Engine failure....
 

Drooze,
Valve contact with a piston won't cause "peening" of a bearing, nor bluing of a crank or a rod. The valve contact came when the piston got loose from the crank. You have two instances of piston to valve contact on one piston. That tells you it was coming loose once and there was minor contact. In order to hurt a rod or a rod bearing, the contact with the valve would have to be severe enough to do massive valvetrain damage, either in one location, or spread over an area.

You had a failure in #3 rod, not in the valvetrain. Period. Either the rod bolts failed because they were either over stressed or not fully preloaded, or the rod got out of round and grabbed the crank and it failed the bolts. Bluing is one of two things, poor lubrication, or a rod bore out of round. The only other possibility, and it is rare, is a crack in the crank, which, by the way causes the journal to be out of round, and usually causes an oil pressure leak.

One other possibility is the wrist pin seizing in the piston, that will either pull the rod throw out of the crank, pull the wrist pin out of the piston, or pull the rod off of the crank. It will be obvious if the wrist pin was seized.

If you've ever seen a timing chain system work, you'll know that what you're describing is nearly impossible. Timing chains don't work that way, and harmonics won't make them work that way.

You are free to believe as you wish, the parts, money, and time belong to you and your father. I've been doing this for 30 years, and Adger has been doing this about as long as I've been alive, that makes for about 80 years of combined experience, and it looks to me like neither of us feel your explanation is plausible.

Re: DP #24 Engine failure....
 

I tend to think the valve hit the piston after the problems with the rod started. Maybe the rod bolts stretched causing the hit.
If the bearing looked good but there was heat showing on the rod could side clearance have been a problem? The bearing should have been toast way before the rod showed heat.

Re: DP #24 Engine failure....
 

Hang in there,

Good Luck :)

Re: DP #24 Engine failure....
 

If you ran the engine to 8000 on the dyno.......I would have to ask if the HP and TQ was still near peak or at peak........Those numbers would indicate if the valvetrain was still stable or going into valve float. What kind of lifters do these engines use? I am sure they are rollers but are they solid rollers or hydrualic rollers? Was the engine looked over carefully after the dyno session? A valvetrain exam and an oil filter cut open and checked? Just some questions here nothing else.

I have seen engines run on a dyno that had an issue during testing and that engine failed soon after it was raced......Not saying that's what happened here but it's just a thought......

How heavy are the pistons and pins in one of these engines? I don't have a real warm and fuzzy feeling about spinning an engine to 8000+ with import I beam rods in it......I would at the very least replace the bolts with the best I could find.......

Re: DP #24 Engine failure....
 

Well, I will only say this in as much as my possible "theory" of how and what may have caused the whole debacle to occur, and this comes from my experience, albeit in a different design engine, we see it happen all the time, at extrodinary revs (usually 12k) with a trans or clutch breakage where it freespins, then the valve contact the piston, on an engine with a stable valve train to 15k in these cases however the damage to the bearings can be seen at times, they are rollers, and different granted, seen it too many times to count, those are however ohc engines, and of older design BUT that is what led me to consider it as a possiblity.

Now......after talking it through with a couple of others on the phone....I still cant say the PTV occured before or after. BUT you are correct and that was one thing I didnt consider it was mentioned to me on the phone, and I think Art mentioned it too. Either when it lost its bearing or.
But it did do pretty massive valvetrain damage, a broken shaft and split the rocker shaft mounts in 2 so it was a pretty substansial hit, that was also what partly led me to believe the rod was still with bearing and solidly affixed to the crank.

The other reason is the location of the hit on the piston IN the exhaust valve pocket at say 2 degrees retrded there is a PTV issue on the exhaust.


In as much as the wrist pin seizure, what is left of the bosses on the piston are clean with no galling. I think it was a "wood chipper" effect of the rotation of the crank afterward removing the pin and rod from the piston. Just from what we see.

To me, the rod failure is a symptom of something, not the cause, I dont think you are saying any different and I have drawn no lines in the sand and am only trying to have a working theory.

But the rod bolt failure and the piston to valve contact is a plausible explanation. The rod bolts both massivley failed and instantly.

The bluing bothers me, its not as bad as Ive seen but its bad.

In closing this thought process, please dont stop or think Ive mad a final decision on anything, far from it, I know more and more possiblities and some things I just didnt think of before this thread was posted.

THAT was part of the goal....

Keep it coming....

Thanks

Chris and Dave

I am uploading pics right now, if there is anything you think seeing would be helpful that isnt show please ask away and Ill shoot it.....and upload it.


I

Re: DP #24 Engine failure....
 

--QUOTE=Rich Biebel;179865--If you ran the engine to 8000 on the dyno.......I would have to ask if the HP and TQ was still near peak or at peak........Those numbers would indicate if the valvetrain was still stable or going into valve float. What kind of lifters do these engines use? I am sure they are rollers but are they solid rollers or hydrualic rollers? Was the engine looked over carefully after the dyno session? A valvetrain exam and an oil filter cut open and checked? Just some questions here nothing else.

Nope still climbing and I didnt like spinning it that fast, so I was the one and the reason that said no more over 72, we can predict fuel and timing from there.

Yes motor was checked after Dyno, all looked good, heads off, no smacks, so it wasnt "earlier" all looked good, even filter was clear of anything but expected break in debris and even that was very light.

They are hydraulic rollers, and are good to at least 8500.....ask Irv and Duell, Jerry, etc........they are amazing to me for a stock piece.

Good salient questions all of them, these are the answers....lol

I have seen engines run on a dyno that had an issue during testing and that engine failed soon after it was raced......Not saying that's what happened here but it's just a thought......

Its a very good point

How heavy are the pistons and pins in one of these engines? I don't have a real warm and fuzzy feeling about spinning an engine to 8000+ with import I beam rods in it......I would at the very least replace the bolts with the best I could find.....

Piston with pin around.620...yeah boat anchors....and the rods 600-620.... and yeah Import beams scare the psheszzz outta me too but right now its the only approved rod, I called a couple of people for this motor and noone could get me anything approved, Eagle was about useless and had no care. K1 is trying but falling into NHRA issues that arent issues that now are...who knows...they are trying. for an H beam anyway.

Well waiting on a couple extra sets of hands here to get somethings done.

I just heard that there is another bolt for these rods. Better, gonna track that down FAST....like real fast.....

AND I will say today the bearings look worse in the light....daylight, so maybe , quite possibly oil starvation was in fact the culprit. The mains have some bluing at the parting lines and some galling . Trying to build another one as well as trying to diagnose is too difficult at the same time. With what I know for sure, what I think I know, some things I didnt want in the other engine but were there, and the clearances being in my opinion and others here including your own too tight.....well.....

For today and tommorow Im going to go strictly back to building what i think should be built.....if it comes apart then its 100% my failure, if it dosent then its my success.....

For certain things like rods, bolts, etc....unfortunatley I have no legal options.....so Im stuck.

All the Pics are here btw, I will leave you with a few "fun" ones.

http://www.flickr.com/photos/newhemi...7623768319716/

http://farm3.static.flickr.com/2695/...44d6bf1c8b.jpg
http://farm5.static.flickr.com/4039/...1da1f8e7ea.jpg
http://farm3.static.flickr.com/2709/...7b7802dcd7.jpg
http://farm5.static.flickr.com/4065/...1cd8e94e4c.jpg

Re: DP #24 Engine failure....
 

Side clearance looked good before chassis dyno....didnt look after but cant imagine that much lunch after engine dyno....looked good was checked , but I just dono, what makes 1 fail faster than another, clearance.........

The rod bolts stretchin could have cause a hit I guess, anything over 080 would have caused an exhaust hit, in the pics though, well for it to hit that square in the pocket it still had to be attached to the rod I think and it was a tdc when it happened, but streched bolts, certianly I think now, didnt before....or a shelled bearing maybe.

The force at which it hit causing the valve train damage....thats whats got me puzzled....

Re: DP #24 Engine failure....
 

looking over the pictures it looks as if the bolts stretched and broke and the rest is damage from rotating mass ,,in one of the pictures of the bearing halfs it looks as if one of the tangs is missing or flat(spun bearing?)(could be caught up in the damage) ,,,one thing i would check of whats left of the 7 rods and pistons is if the big ends are still round ,,maybe the rpm is taxing the bolts or the bottom half of the rod cap is just flexing egg shape ,try to retorque the bolts to see if they will turn(they shouldnt)

i hate to see that damge on all the hard work and money that go's into this stuff

just my 2 cents gmonde

Re: DP #24 Engine failure....
 

I think the rod bolt failure is the cause. Thats a heavy piston and rod. And when they change direction on the end of the exhaust stroke. There is a lot of force to make the change.

Ninjas Caused DP #24 Engine failure....
 

Art....I now would agree 100%.....after what Alan, and some others have said, and thinking and rethinking it through, as well as getting the spec on the bolts that were in there, AND yesterday I didnt pull it down, the old man did I was busy with other things, he left 2 rods in and the bolts were in fact "loose" or as gmonde said, well 1 on each "turned" it shouldnt have, no doubts....

Im still a little at a loss as to how exactly I did the valve train damage but if it let loose at the very top of the stroke which it would have well I guess thats where the PTV contact occured....it must have "bounced" then off that valve as there is no other damage to the chamber or piston and headed down to the "rod chipper"

I looked very carefully at the bolt shears 1 is clean the other torn to a 45 degree peak across the plane.

So I may have ovrthought the living ****e out of it, but thats ok......"I get by with a little help from my friends".......and I mean that to all that a)Talked me through, down and over it. b)were constructive and helpful and that was every single response in this thread. every single one......

Thanks to all the CR people and I mean that....

I had only what I have seen before, and it was a "chicken and egg problem" and it didnt meet occams razor, this does and it shows to be true.

The rods are actually round (im suprised I had heard others engines after being run were not) AND the rods didnt break, the bolts did, much easier to find a suitible high tensile replacment than get a rod approved.

I have 2 sets of bolts here (good) I am shocked at how close they measure within .007 each ?!? across 16....maybe its a batch thing. BUT the bolts that came out of the engine ? I quit at 5, I could SEE differences....now I didnt measure them new....but that seems like a lot of variation....Ill bring em in a bag......

2 days ago my daughter warned me what caused it and I didnt listen....we were driving down the road past a stretch of wooded marshlands, she said "daddy I know what lives in there" she exclaimed....I said really, expecting to hear owls , turtles....NINJAS, they live in the TREES ! I almost wrecked laughing....She just turned 4....a bit later in the day something was amiss and she said matter of factly....Ninjas did it.....

You would THINK Hemi Ninjas wear orange and would be easy to spot.....hmmmmm......damm ninjas...

Thanks all.....see Im trainable :) And grateful.......

The egg came first it would look the the chicken smacked the valve...

Re: DP #24 Engine failure....
 

See my next post....oops...

Re: DP #24 Engine failure....
 

Wow.....that is a terrible looking mess of parts......

From what I see...it appears to be a major failure without a spun bearing or anything related to friction in the rods or crank.

Difficult to determine what broke first as most of it is collateral damage after the initial part failure....

Is it possible there was contact with something you overlooked at very high rpm? Like a rod hitting the cam or the block somewhere......it would easily explain the abrupt failure of the rod or rod bolt .......

Something either flat broke or something was hitting something and caused the breakage......

The parts don't look to be poor at all...... even the rods look fine and the bolts appear to be decent...maybe std material, and they are usually pretty fair.....

Anytime I have an event like that I get rid of the busted up stuff as quickly as possible.....I have this thing about blown up parts....I don't want their bad Karma to attach itself to any new parts I get.......SCRAP that mess ASAP......Learn what you can from it and JUNK that stuff......LOL

Re: DP #24 Engine failure....
 

The pistons are not heavy, neither are the rods. You should try my stuff. And we go through the lights at over 7800 RPM.

STOP building another engine until you KNOW what went wrong. Trust me on this, I've been there. In your rush to get back to the track you will learn nothing, and spend thousands. I know, I did it. What you are going to do if you keep rushing is waste a year you could be learning, and put yourself 1-3 years behind. You will not catch up easily. Stock Eliminator is different than anything you've done.

Re: DP #24 Engine failure....
 

6.1 Hemi.....= 370 cubes....What is the bore and stroke.....What is the main diameter and rod diameter....what is the rod length.....

4.055 3.580 370 8 6.200 12.6-1

Pretty straight forward looking engine specs.....not unlike a small block chev...with lots of compression.......Not your average street cars compression ratio!

Piston appears to be a Semi Hemi design...not a true Hemi.....

What is the cam lift......

385 370 .0135AB Dome .137 14.8cc 2100/1600 584/552 Beehive .039

Killer valve sizes and cam lifts.....easy to see why it runs as fast as it does....

What do the heads look like.....what is the intake and exahust port CC's and what do the heads flow.....port shapes? All this stuff says a lot about the usable rpm range of the engine.

If the heads are even reasonably decent.....it makes a lot of power.....and obviously they are from the numbers run by others.....


Doug Duell and Irv Johns have run some 9.80's at what weight?

370 cubes is pretty small to be running 9.80's at 132-133? I am guessing they are spinning them pretty hard to run those kinds of numbers....so my educated guesswork says lots of RPM might be normal for one of these.....

Re: DP #24 Engine failure....
 

What does the #3 cylinder wall look like? - any marking or scoring?

Re: DP #24 Engine failure....
 

Rich Biebel;--6.1 Hemi.....= 374 cubes....What is the bore and stroke.....What is the main diameter and rod diameter....what is the rod length.....

4.055 3.580 370 8 6.200 12.6-1

Piston appears to be a Semi Hemi design...not a true Hemi.....

Correct

What is the cam lift......

385 370 .0135AB Dome .137 14.8cc 2100/1600 584/552 Beehive .039

What do the heads look like.....what is the intake and exahust port CC's and what do the heads flow.....port shapes? All this stuff says a lot about the usable rpm range of the engine.
http://www.allpar.com/mopar/images/n...i/5.7-head.jpg

They flow about 300in 200ex @600 on a stock SRT8 head....I dono the DP head but there is no port difference only valve size on in 2.100 instead of 2.08

Com cc about 79, dont recall ports at moment...

I can look some of this stuff up on the NHRA Engine blueprint guide specs.....but I thought you could tell me some of this stuff.....

Doug Duell and Irv Johns have run some 9.80's at what weight?

Not really sure, rumors only other than unsanctioned runs and weights but that was shared in confidence and I keep that above all else....

Well its above 3270 ship+driver and I believe we are the lightest by about 40-50 lbs of any of the DP's but....well...we spent a lot of time doing that , and things like 8.75 and 904 vd dana and protrans...

Just interested in knowing some of the particulars on one of these engines for comparison to others.......

374 cubes is pretty small to be running 9.80's at 132-133? I am guessing they are spinning them pretty hard to run those kinds of numbers....so my educated guesswork says lots of RPM might be normal for one of these.....

There isnt a DP person running I have heard of spinning one UNDER 8k in a run of competition.....maybe there are and if they want to speak up....hey....lol....but everyone I know is turning it that and FASTER !

Re: DP #24 Engine failure....
 

Some where the rings mashed when the wrist pin was ripped out, but other than that no worse than the rest from parts of the wrist pin shrapnel rubbing up and down.

Re: DP #24 Engine failure....
 

What kind of piston pin lock was used? Hard to tell, looks like a wire lock? - Looking at the piston close up shots, there might be a possibilty that the near side piston pin lock came out - look at the near pin bore, looks in good shape, the far side looks like it was holding on for dear life as the pin was creeping out and finally let go, some of the piston damage is after that happened.

Re: DP #24 Engine failure....
 

Correct and I would agree, just dont think that happened until the rod went down and thing hit the "rod chipper" ,wire lock as well correct.

Re: DP #24 Engine failure....
 

Well, that 1 pin bore is not going to hold that piston, is the #3 exhaust valve bent?

Re: DP #24 Engine failure....
 

Alan, thanks for the advice and under "normal" circumstances or if it was one of my camera's or a bike of mine alone I would wait.

BUT in our case time is not an option, its something neither me or my father are promised tommorow. We tend to learn on our feet.

And thanks to the directions, and advice here on CR and from people met here on CR alone (we me and the old man are kinda recluses because well we are busy) well....we do know what went wrong, the rod bolts failed. AND now we have a solution thanks to the "DP Confederation" as it were, Someone called and said someone just found an off the shelf answer from another brand L19 220kpsi...should be sufficient :) So I called them and they told me I checked Summit and Voila in stock...so tommorow a grueling 15 minute trip to Summit .... I will have to recheck the rod clearances as the spec is tighter on them and Im afraid of the crush, 63 vs 89 lbs torque....(and no thats not what Im going to install them by but) its enough of a baseline it could change my clearances possibly.

We work in parrelel tasks always me an the old man and were good at it togehter.....

Thats how we put the DP together in as short a time as we did, nothing painted in a corner everything happening at the same time.

AND we learn by doing, and failing and doing again, until we get it "right" we both him and I have a BAD habbit of losing interest at that point when we hit "top of the game" Thats what we both like and keeps us interested in racing of one form or another we have no illusion we will ever be the top of the chain.

We enjoy all of it, litterally all of it, we find ways to find enjoyment even in failure.

And were both too stupid to quit even when we should......so well do as we can and the cards have been dealt, well plug away with the determination it takes.

We learn by doing I guess is my point and we dont have the luxury because of circumstances to approach it in a ..... slower ? fashion, lest we may not have the chance at all.

Re: DP #24 Engine failure....
 

Nope....oddly no not really.....a little runout more than it had before but not "bent"

Re: DP #24 Engine failure....
 

Chris I"m sure you know this but. Make sure you follow the manufacturers instructions on what lube to use on the bolts. And if they are bolts and nuts make sure you resize the big end after putting in the new bolts.

Re: DP #24 Engine failure....
 

That rpm level is generally reserved for SS'ers.......If that is where your target rpm ceiling is......you need to be sure everything is as good as it can be.....

RPM kills parts..........and the dangers go up exponentially as the rpms increase......I don't see anything much different on that engine than any other engine. Small block Chevy Stockers don't generally turn 8000+ rpm although some might.....and all would if they could and stay in one piece....and the engine continued to make more power at those higher rpms.

I am not so sure that 8000+ rpms is a good way to race and expect to make it thru multiple races. Generally staying in one piece is required to be successfull at racing. Stocker engines generally last a long time. Every run is not a record attempt on the ragid edge..........or one where you attempt to rotate the Earth......If you wish to race like that.....more power to you.......but making it to the next round is always a goal.....It's simple...ya can't race if your broke.....

Re: DP #24 Engine failure....
 

Who's pistons are those? - if the exhaust valve is not bent, why did it contact in just those two spots? - is the exhaust pocket angle the same as the head valve angle?

Re: DP #24 Engine failure....
 

Id like to run it lower and with what I think we have as a torque advantage Im hoping we will, my target was set it to 7500....and go from there. at 7200 shift point, (I think) stepping on the limiter all the way in 1 and 2 (set shift and limiter to same on accident) I ran a 10.87 with a soft, soft bad lauch (driver error) sooooo.....dono....

The 8k on this "spin" was unintentional....it was an error....

I agree, I do know we will start out trying a heck of a lot lower , but knowing what others are doing, and they have experienced these well.....Irv Johns, Duell, and others its not like theyre fresh, GRANTED they had better more experienced builders build there motors.....so...

Re: DP #24 Engine failure....
 

I heard different from a good source. Even if that were true, my suggestion to you is the same as it was for Atlanta, run a little on the soft side until you fully understand your combination.

Re: DP #24 Engine failure....
 

Check....like I said there may be...I just hadnt heard of em :)

I plan to/hope to....that was why I pulled it back on the dyno to 72 after engine #1.....I should have left the limiter at 8k.....not 82 as it was...I dont think it would have mattered in this case even at 78 it could/would have spun up another 200 free....

But at Houston (IF we get there...) well....light and easy...gotta get it to Vegas for the old man to blow up :) (hell LOVE that when he read it tommorow....trust me....ok maybe not...lol)

Re: DP #24 Engine failure....
 

When you loose a rod bearing the extra clearance between the crank and whats left of the bearing and rod start acting like a slide hammer and all the damage you have is the results. This slide hammer effect snaps pins and pops the pin bosses out of pistons. It can also snap rod bolts. hummm 8,000 rpm = 133.3333 times a second that the slide hammer hits. Looks to me like you simply lost a bearing.. show us a picture of what is left of the bearing.. that might be all we need to see.

Re: DP #24 Engine failure....
 

I didn't see any spun bearings in the pics on the site the link goes to?

Are there more pics?

Re: DP #24 Engine failure....
 

The only potentially spun bearing was #3, the #4 rod is sitting in its place in the pics (the Z'd rod)

All the rest of the journals are as clean as can be.

The engine drank garbage, and its hard to tell on the bearings (to me) what was caused by that and when.

Ive got another "issue" now that well isnt a product of anthing other than incorrect information. Note to self, when something "smells" bad spend the time to dig a little deeper not matter what everyone says (not everyone here) but it could have been a "misunderstanding", and a typo on Mopars part, or a change a bulletin wasnt recieved on.....and well.....a difference in early or late/other DP motors ? wont know till I talk to Stanton tommorow........no "good" solution that isnt really a "hack" in the time I have to make it to Houston. 1 chance....1 very small chance.....

Oh well...itll be "right" in the end just not by tommorow.